Rapp was born in Zürich. At a young age he became a Swiss child actor, including starring in the lead role in the 1941 film Das Menschlein Matthias.[2][3]
As an adult, Rapp performed as a female impersonator and was a personal friend of Karl Meier. Rapp worked as a hairdresser and later was a teacher at the hairdressing school of Jonny Fahrny.[4]
In 2003, Rapp and his longtime partner Ernst Ostertag became the first gay men to register a domestic partnership in Switzerland. They first met at the Barfüsser-Bar in 1956.[5] Rapp came out officially to friends and family, alongside his partner, at their joint 70th birthday party in 2000.
In 2018, Rapp chose to end his life by assisted suicide after a battle with kidney disease.[6]
